OtakuGirl❤'s manga / #Ｏ(≧∇≦)Ｏ(151)

This is definitely one of the most mature concepts of yaoi I've ever read. The fact that they grew to be alone without each other and didn't end up together with a final fling letting them know that they are "destined for each other" is a rare occurence. Their now walking on their own paths with Subin having Jun to rely on and Hyunwoo pursuing his passion.